An adaptive time delay estimation with direct computation formula

Abstract

The problem of estimating and tracking time delay between signals received at two spatially separated sensors is essential in varied fields. For example, in the sonar system, the information of time delay can be used to localize the radiating source. In real-time processing, an adaptive time delay estimation (TDE) method with desired performance and less computational time is preferred. In this short paper, a simple and efficient method is suggested for TDE. This is done by employing a direct formula coupled with the adaptive LMS TDE algorithm. The advantage of the presented method, in terms of the accuracy as well as execution time, over the conventional lookup table method and interpolation formula method is shown in both the stationary and nonstationary time delay environments. Moreover, the capability of estimating time delay in an environment with multipath propagations is investigated.

A new adaptive constrained LMS time delay estimation algorithm

“…To circumvent the drawback described above, recently, Chern and Lin [6] proposed an efficient and simple scheme for non-integer TDE, which is referred to as the direct delay estimation (DDE) formula. Here, the DDE formula does not involve the interpolation formula and the look-up table proposed by Ching and Chan [5].…”

“…Here, the DDE formula does not involve the interpolation formula and the look-up table proposed by Ching and Chan [5]. In [6], it was shown that, for non-integer TDE, the DDE formula approach is superior to the look-up table method in both performance and computation complexity. However, the performance of the DDE formula highly depends on the relative values of the weight coefficient with the largest amplitude and its two adjacent weight coefficients (in both sides).…”

“…As described earlier, the performance of noninteger TDE is highly related to the convergence behavior of the estimated weight coefficients. Under general conditions, the weight coefficients of the FIR filter estimated by the conventional LMS TDE algorithm [5][6][7], are not sufficient enough to converge to their true values. To improve the convergence speed of the weight coefficients to the true values, in this paper, a new constrained LMS TDE algorithm is developed by using the constraint that the sum of the squares of the weight coefficients of the FIR filter equals unity.…”

Automatic identification of sound source position employing neural networks and rough sets

“…Most of them are based on estimation of the sound source position on the basis of signals received by microphones in the matrix, including cross-correlation techniques (Brandstein, 1997), adaptive filtration (Chern and Lin, 1994) or computation of relevant eigenvalue vectors and matrices (Berdugo et al, 1999). In turn, in the case of tracking or localizing a number of sources, the maximum likelihood-based methods are exploited (Ziskind and Wax, 1988) representing the statistical approach.…”

An Adaptive All-Pass Filter for Time-Varying Delay Estimation

“…As such, their accuracy depends on the precision of these methods and can be sensitive to noise. Hence, in [12] the direct delay estimation (DDE) technique was proposed as an alternative, overcoming the need for interpolation in the calculation of the delay.…”